JP2850135B2 - Manufacturing method of hydrodynamic groove bearing - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a hydrodynamic groove bearing in which a hydrodynamic groove is formed on a bearing surface of a shaft.

[Prior art] Conventionally, when forming a dynamic pressure groove in a bearing, cutting and rolling were performed, and the shaft was formed with a dynamic pressure groove formed by etching, cutting, and rolling using a photomask. .

When a dynamic pressure groove is formed on a bearing by cutting or rolling, the cost is high, and it is difficult to manufacture a small-diameter bearing having an inner diameter of about 3 mmφ.

[Object of the invention]

The present invention has been made in view of the above-described drawbacks, and has as its object to propose a method of manufacturing a dynamic pressure groove bearing in which a dynamic pressure groove bearing can be easily manufactured at low cost, and a relatively small diameter object can be easily manufactured.

[Configuration of the invention]

The present invention is a method of manufacturing a dynamic pressure groove bearing by using a powder metallurgy method for a bearing material made of a sintered oil-impregnated bearing material, wherein the sizing rod on which the groove is formed is lower than the sizing rod material. Harden the above bearing material in the circumferential direction
After the groove is transferred to the bearing material by pressing in a state where a dividing surface is formed at more than one place, the bearing material is divided at the dividing surface and removed from the sizing rod, and the bearing material is stored in the housing. And forming a bearing.

〔Example〕

Hereinafter, the present invention will be described with reference to the illustrated embodiments. 1 to 4 show a manufacturing process of the hydrodynamic groove bearing. FIG. 1 shows a sizing rod 3 having a groove 3a on the outer peripheral surface.
And bearing materials 1 and 2 in which grooves 1a and 2a are formed by the sizing rod 3. This bearing material 1,2
Are formed by powder metallurgy and can be plastically deformed. In addition, the bearing materials 1 and 2 are formed of a material having a lower hardness than the sizing rod 3, and the bearing materials 1 and 2 are pressed against the sizing rod 3 so that the groove of the sizing rod 3 is formed.
3a is transferred to bearing materials 1 and 2 and grooves 1a and
2a is formed. In addition, these bearing materials 1 and 2
The shape is such that a cylindrical shape is divided at two symmetrical points, that is, a semi-circular shape.

The procedure for forming the grooves 1a and 2a for generating dynamic pressure in the bearing materials 1 and 2 will be specifically described below. First, the bearing materials 1, 2
Is manufactured by a powder metallurgy process (not shown).
That is, the bearing materials 1 and 2 are produced by the steps of powder molding → sintering → primary sizing. On the other hand, a herringbone-shaped groove 3a is formed in advance on the sizing rod 3 by etching or rolling. Next, the bearing materials 1 and 2 are combined from both sides of the groove 3a position of the sizing rod 3 having the groove 3a as shown in FIG. 2, and the bearing material 1 is inserted into the through hole 4a of the die 4 as shown in FIG. , 2 and sizing rod 3 are inserted. Then, a punch 5 and a lower punch 6 are inserted into the through holes 4a from above and below the bearing materials 1 and 2 placed in the through holes 4a of the die 4, and are applied to the bearing materials 1 and 2, respectively. Thereafter, as shown in FIG. 4, the upper punch 5 and the lower punch 6 are pressed by the load P. In this operation, the bearing materials 1 and 2 are compressed, and the grooves 1a and 2a for generating dynamic pressure are transferred to the inner peripheral surfaces of the bearing materials 1 and 2.

The bearing materials 1, 2 on which the grooves 1 a, 2 a for generating the dynamic pressure are transferred and formed in this manner are taken out from the through holes 4 a of the die 4 and are also taken off from the sizing rod 3. Then, as shown in FIGS. 5 and 6, the two bearing materials 1 and 2 are brought into a set while being in contact with each other, and are lightly pressed into the housing 7. The hydrodynamic groove bearing 8 formed by lightly press-fitting the bearing materials 1 and 2 into the housing 7 is taken into a bearing holder such as a motor and is combined with a separately prepared shaft with a small gap. .

As described above, the bearing materials 1 and 2 are formed by the low-cost powder metallurgy method, and the dynamic pressure groove bearing 8 is manufactured using the bearing materials 1 and 2 and the above-described configuration and method.
It is easy to manufacture the dynamic pressure groove bearing 8 which is very low in cost as a whole. In addition, according to the above-described method, by using the sizing rod 3 having a small outer diameter, a dynamic pressure groove bearing having a relatively small diameter can be easily manufactured.

When the bearing materials 1 and 2 are made by powder metallurgy,
It is soft and easily plastically deformed, and has the effect of improving transferability.

Further, if the bearing materials 1 and 2 are formed into a semi-circular shape divided by two divided surfaces, the bearing materials 1 and 2 can be separated from the sizing rod 3 by being divided at the divided surfaces, and can be used for generating dynamic pressure. The grooves 1a and 2a can be easily removed without scratching. Further, by incorporating the transferred semicircular arc bearing materials 1 and 2 into the housing 7 and the like again, a perfect circular dynamic pressure groove bearing can be easily formed.

The bearing materials 1 and 2 may be a sintered oil-impregnated bearing material.

7 to 10 show modifications of the method of dividing the bearing material and the division plane.

FIG. 7 shows bearing materials 1, 2, and 9 divided into three parts.

 In FIG. 8, the division surface is formed as a triangular wave-like surface.

 FIG. 9 is formed by a stepped dividing surface.

FIG. 10 shows a bearing material 10 in which only one division surface is formed.

The bearing materials 1 and 2 of the hydrodynamic groove bearing 8 are described as examples of sintered bearing material or sintered oil-impregnated bearing material by powder metallurgy method. It may be a sintered oil-impregnated bearing material formed by the method or a bearing material made of a plastically deformable material such as plastic.

〔The invention's effect〕

The present invention uses a sintered oil-impregnated bearing material that is easily plastically deformed as a bearing material, so that it has excellent transferability, and a groove formed in sizing or the like is accurately transferred. In addition, even when housed in the housing, it is easy to obtain the inner diameter dimensional accuracy. Therefore,
The groove can be formed with a uniform depth, and as a result, the dynamic pressure performance is stabilized. Moreover, since the sintered oil-impregnated bearing material is formed by compressing metal powder and sintering (heating) the metal powder, pores are present throughout the bearing. The holes hold the lubricating oil. Therefore, since the circulation of the lubricating oil is promoted with the rotation of the shaft, etc.,
The shaft can be supported very smoothly. Further, since the bearing material is pressed against the sizing rod in a state where the dividing surface is formed at one or more locations in the circumferential direction, when the bearing material is removed from the sizing rod, the removal is easy and the groove can be prevented from being damaged.

[Brief description of the drawings]

The drawings show an embodiment of the present invention, and FIGS. 1 to 4 show the manufacturing steps of a hydrodynamic groove bearing. Figure 1 is 2
FIG. 2 is an exploded perspective view in which grooves of a sizing rod are transferred to two plastically deformable bearing materials formed in a semicircular shape on two divided surfaces. FIG. 2 is a sizing rod before the grooves of the sizing rod are transferred. Exploded perspective view of the bearing material and the third
FIG. 4 is an exploded perspective view showing a sizing rod and a bearing material placed in a table, and an upper punch and a lower punch are not inserted into the table. FIG. 4 is a perspective view in which a load is applied to the upper punch and the lower punch. The figure is an exploded perspective view of the bearing material and the housing with the groove transferred, FIG. 6 is a perspective view of a hydrodynamic groove bearing in which the bearing material is lightly pressed into the housing, and FIG. FIG. 7 is a perspective view of a bearing material divided into three parts, FIG. 8 is a perspective view of a bearing material having a triangular wave-shaped dividing surface, and FIG. 9 is a stepped division. FIG. 10 is a perspective view of a bearing material having only one divided surface. 1, 2, 9, 10 ... bearing material, 3 ... sizing rod, 1
a, 2a, 3a ... groove, 7 ... housing, 8 ... dynamic pressure groove bearing.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16C 33/14 F16C 17/02 B22C 5/00

Claims (1)

(57) [Claims] 1. A method of manufacturing a dynamic pressure groove bearing by using a powder metallurgy method for a bearing material made of a sintered oil-impregnated bearing material, wherein a sizing rod having a groove formed thereon is less than a sizing rod material. Use the low hardness bearing material
After the groove is transferred to the bearing material by pressing in a state where a dividing surface is formed at more than one place, the bearing material is divided at the dividing surface and removed from the sizing rod, and the bearing material is stored in the housing. A method of manufacturing a hydrodynamic groove bearing, wherein the bearing is formed by forming the bearing.